利用锥形束CT和激光快速成型技术制作牙颌模型的可靠性分析

The reliability of dento-maxillary models created by cone-beam CT and rapid prototyping:a comparative study

目的:分析建立上牙颌模型的锥形束CT和激光快速成型技术的可靠性。方法:收集20例正畸患者的牙颌石膏模型和锥形束CT数据,将CT数据重建成三维数字模型(即3-D模型),并应用激光快速成型技术加工出牙颌树脂模型(即RP模型)。对石膏、3-D和RP模型分别进行牙冠宽度、牙弓宽度、牙弓长度等测量,利用SPSS17.0软件包进行统计学分析。结果:3种模型之间,除牙弓宽度外,其余大部分指标具有显著差异(P<0.05);3-D模型值普遍小于石膏模型和RP模型(P<0.05);RP模型与石膏模型之间大部分指标不具有显著差异(P>0.05);RP、3-D模型与石膏模型之间的回归系数均具有显著差异(P<0.01),且前者普遍大于后者。结论:3种模型之间具有高度一致性,存在可为临床所接受的差异,提示3-D模型和RP模型具备替代石膏模型的可能性,从而节约存储空间,提高工作效率。

PURPOSE： To analyze the reliability of the dento-maxillary models created by cone-beam CT and rapid prototyping（RP）.METHODS： Plaster models were obtained from 20 orthodontic patients who had been scanned by cone-beam CT and 3-D models were formed after the calculation and reconstruction of software.Then,computerized composite models（RP models） were produced by rapid prototyping technique.The crown widths,dental arch widths and dental arch lengths on each plaster model,3-D model and RP model were measured,followed by statistical analysis with SPSS17.0 software package.RESULTS： For crown widths,dental arch lengths and crowding,there were significant differences（P〈0.05）among the 3 models,but the dental arch widths were on the contrary.Measurements on 3-D models were significantly smaller than those on other two models（P〈0.05）.Compared with 3-D models,RP models had more numbers which were not significantly different from those on plaster models（P〉0.05）.The regression coefficient among three models were significantly different（P〈0.01）,ranging from 0.8 to 0.9.But between RP and plaster models was bigger than that between 3-D and plaster models.CONCLUSIONS： There is high consistency within 3 models,while some differences were accepted in clinic.Therefore,it is possible to substitute 3-D and RP models for plaster models in order to save storage space and improve efficiency.